1. Field Of The Invention
The subject invention generally pertains to speakers and more specifically to those operating in the lower frequencies of around 30 Hz.
2. Description Of Related Art
High quality speakers typically operate at a system Q (Q.sub.tc) of between 0.5 and 1.0. This generally provides a nice uniform, flat response curve. Bandpass filters used in such systems have relatively small inductors to provide a low pass corner frequency that is typically well over twice the system resonance (Fc). The greatest disadvantage of such systems is that with the low Q.sub.tc a significant portion of the lower frequency response is lost. A secondary concern is the loss in efficiency, again due to the low Q.sub.tc.
Many inexpensive, low quality speakers operate with a much higher Q.sub.tc. Although such systems are very efficient at delivering the most sound for a given input, the sound is usually very distorted and comes across as a "booming" sound. The response curves typically have an annoying peak near its resonant frequency
Still other speakers achieve a broad low frequency response by way of enormous enclosures which typically provide a low system resonant frequency. Various baffle schemes are also used. However, such mechanical means of capturing the low frequencies are generally more expensive to produce.